中文摘要：

为满足开放式数控系统的发展要求，开发了一种基于实时以太网Ethernet for Manufacture Automation Control（EtherMAC）开放式运动控制系统。EtherMAC主节点基于标准工业计算机，无需专用网卡和硬实时操作系统，从节点基于可编程逻辑门阵列（field programmable gate array，FPGA）硬件逻辑，不依赖专用芯片，从而在硬件结构上保证了系统的开放性。EtherMAC通过选取网络中第一个从节点管理网络的通讯周期和分布时钟，并利用以太网的巨大带宽将IPC强大运算能力和底层FPGA的硬实时特性高效地结合在一起，使系统主节点在软实时的操作系统支持下即可获得严格实时的通讯周期控制。实验结果表明，EtherMAC可以在Windows CE系统上获得小于1ms的通讯周期，并且其同步精度可以保证在100ns范围内，满足多轴运动控制系统的实时同步需求。

英文摘要：

A real-time Ethernet named EtherMAC （ Ethemet for Manufacture Automation Control） was developped for open computer numerical control system. A standard industrial personal computer （IPC） based master node and field programmable gate array （FPGA） based slave nodes were employed in EtherMAC, as neither dedicated network interface card （NIC） nor application specific integrated circuit （ASIC） chips were mandatory, the system was open in hardware architecture. The computation ability of IPC and hard real-time property of FPGA were combined together with Ethernet in this way. By adopting the first slave node to manage the communication and distributed clock, time critical performance could be achieved even the master node only with soft real-time performance. Experimental results showed that communication period less than 1 ms and synchronization precision within 100 ns could be achieved by EtherMAC, which were enough for motion control systems demanded critical real-time and synchronization.